Conventional vehicle lights utilizing an LED light source have been developed to be provided with various optical systems and system configurations, thereby providing a desired light distribution pattern. For example, a vehicle light 200 as shown in FIG. 1 utilizes a plurality of optical units including light converging units 210, middle diffusion units 220, a large diffusion unit 230, and the like. The vehicle light 200 configured as described above can provide a spot light distribution pattern P1, a middle-area light distribution pattern P2, a wide-area light distribution pattern P3, and the like partial light distribution patterns, thereby forming a synthesized light distribution pattern as a whole. (See, for example, Japanese Patent Application Laid-Open No. 2005-294166.)
In the above vehicle light 200, however, the respective optical units, including the light converging units 210, the middle diffusion units 220, and the large diffusion unit 230, are typically separately designed with different specifications. Furthermore, the optical units typically have respective LED light sources separate from each other. Accordingly, there are problems in that design burden and the number of components increase, thereby increasing the entire cost.
The presently disclosed subject matter was devised in view of these and other problems and features and in association with the conventional art. According to an aspect of the presently disclosed subject matter, a vehicle light can be composed of a fewer number of components when compared with similar conventional vehicle lights, while being configured to suppress cost increase in terms of design and part number.
Further, a vehicle light utilizing a cylindrical lens has been proposed, wherein the vehicle light is provided with an optical member, in particular, a light shielding member with a specific shape so that a desired light distribution pattern is formed. (See, for example, Japanese Patent Application Laid-Open No. 2002-245816.)
For example, suppose that if a vehicle light with a projector type optical unit utilizes a toroidal lens or a cylindrical lens, a plate light shielding shutter having a straight upper edge is adopted. In this case, since the focus of such a toroidal lens is a point focus or a group focus having focuses in an arc shape (strictly, due to the shape of the toroidal lens), light beams may be disadvantageously distributed in an area P1R as shown in FIG. 19 above the horizontal line H-H and near the opposite or oncoming vehicle road side, leading to generation of glare light.
The presently disclosed subject matter was devised in view of these and other problems and features and in association with the conventional art. According to another aspect of the presently disclosed subject matter, a vehicle light, even when utilizing a toroidal lens or a cylindrical lens, can prevent or suppress the generation of glare light that may arise due to a light distribution located above the horizontal line H-H and near the opposite vehicle road side.
Further, in a vehicle light utilizing a projector type optical unit or a light converging and imaging lens (for example, an aspherical lens, a toroidal lens, and the like), as shown in FIG. 11, suppose that the light beam Ray1 from the LED light source 10 (including the case where Ray1 includes direct light from the LED light source 10) enters the lower-half lens portion Lb below its optical axis from the diagonally upper side. In this case, the light beam Ray1 may be diffused and its blue component Ray1B (having longer wavelengths) may be refracted and projected in a diagonally upward direction by the action of the lower-half lens portion Lb. This configuration can distribute the light beam Ray1B near the cut-off line CL of the light distribution pattern as shown in FIGS. 12 and 13, meaning that the area is colored blue. This colored area may impair the light distribution pattern in terms of white color specification in accordance with a certain regulation as shown in FIG. 14 (the mark triangle is positioned outside the regulated area for white-color).
The presently disclosed subject matter was devised in view of these and other problems and features and in association with the conventional art. According to still another aspect of the presently disclosed subject matter, a vehicle light can prevent or suppress the generation of colored area (for example, blue) in a desired light distribution pattern near its cut-off line caused by the direct light from an LED light source or reflected light therefrom that enters a lower-half portion of a lens below its optical axis from the diagonally upper side. The optical axis can be a central axis along and about which light is centrally directed by the lens.